Fig. 6.5. Left: Cat-faced scars in mature red pines at Itasca - probably a legacy of past fires and the localized attacks of bark beetles
within scorched regions of the bole. In these trees, and many others at Itasca, the cat-faced scars bear evidence of multiple wounding
events that were separated by years or decades (probably a sequence of fires followed by beetle attacks). Each wounding event tends
to expand the perentage of the trunk that is girdled and increases the amount of wood that is exposed to future fires. Right: one of
many trees at Itasca that died from ignition of the exposed wood in a cat-faced scar. This is the endpoint of the positive feedback cycle
represented in Fig. 6.7. The downed tree will increase the local fuel load for subsequent fires and increase the probability of fire
damage to adjacent trees (Fig. 6.8). Fig. 6.4 shows the early formation of cat-faced scars